I always loved the sound of a good BOV. I often hear imports with turbos rev their engines at a stop light and get the blow off valve to vent. I could never get the BOV in my TT IROC to go off unless I was driving. I didn't have to hit boost, but at least load the engine long enough to start to spool the turbos. Does anyone know how I can make my car do this? Is there a special BOV these guys are using? Its cool when you can let people know your car has a turbo without even moving.

 

I think the key to the import guys success on this front is their drastically undersized turbos.. I can't really get my 2.8 to blow off-load either.

 

Yeah pretty much any turbo that will spool hard in neutral is either teeny weenie or VERY efficient. for instance, the GT25R will support 350+ horsepower on a 2.0L motor (SR20DET for instance) but its throttle response, Spool time, is INSANE on those cars.

I cant get my turbos to "spool" in neutral, but I can still get my BOV's to SOUND in neutral. not loudly, of course, because there is no boost in the intake tract, but they still open up enough to hear them. Im using 2X Stock DSM BOV's.

Wana hear something funny, we got stupid one night and went to WAL-MART and on a whim bought some TURKEY whistles. duct taped them to the BOV's and OMFG it was hilarious. gota get some video...

 

Also they type/style of BOV will dictate how much noise it makes and wwhen it makes it... For instance if they have a cheap POFS TurboXS NOISY version one that is set up to blow at 5 PSI combined with a small turbo it will do that....

I have a turbonetics godzilla and for the RICERS they actually make what turbonetics calls a HORN that bolts onto the end of it to make the BOV sound LOUDER.... LOL Me I dont really care what it sounds like.. as long as it works..

 

greeat. a new fad... turbo whistles....

 

Thats all the godzilla HORN is ...basically looks like a whistle...

 

There is a video going around of a guy who taped a duck call whistle to his blow-off valve. Kind of stupid and silly. Did it for laughs from what I understand.

http://home.comcast.net/~filewhore3/turkeybov.mpeg

 

I had a ***** drive by me the other day with a MEAN blow off valve. It wasn't a PSHHHHHHHHH it made a whipple noise like a lot of grand nationals and it sounded great. He piped some kid at a light and it didn't do anything but when he did his 1-2 shift it was insane sounding.

 

Oh man, that turkey BOV video has me crying. I am not to sure why that was so damn funny to me!

 

thats the only cool sound that i think an import makes! i hate the sound but love the sound a turbo blowing off!

 

I think the noise you often hear GNs make is actually the sound of no BOV. That flutter you hear when they lift is the compressor surge.

Personally, I like the sound of compressor surge, but I don't like that it can cause possible turbo damage and you loose turbine speed that must be regained after a shift. Most GN guys don't use a BOV since they are running autos.

 

My neighbor's '95 Twin Turbo Supra Corolla has twin HKS sequencial blow-off valves, and I had to admit that they sound great. Those BOV's make a space like sound combined with a hard PHSSSS that make it sound cool and at the same time serious. What I dislike about those BOV's is the fact that they have plastic internals and recently one of the BOV got stuck on his car, never happened to me on my Tial BOV Nevertheless the BOV's on his car sound great and give the car along with the carbon fiber rear spoiler that Fast & the Furious look and feel. So sad that such a nice car has to eat dust from his neighbor's GTA

 

Thats right! You show him turbo V8 muscle!

 

theres a local GN that someone swapped to a manual.

i really want to meet the owner and get a better look at it.....




:lala:

 

??? 95 Twin Turbo Supra Carolla??? What the heck is that?

 

so your telling me that if i run an auto, a BOV is not necessary?

 

A BOV isn’t necessary, period.

 

The biggest advantage of the BOV is that the turbo can stay up to speed during a manual trans shift. This is possible because the BOV allows the compressor to keep airflow up while the throttle plate is shut. With a BOV, boost can be had almost imeddiately after the shift, instead of waiting for the turbo to re-spool. So with an auto, the need for a BOV decreases.

Some also say that the compressor surge is damaging to the turbo bearings, but that seems to be up for dispute.

I agree with Mark that a BOV is not necessary, especially for drag racing (where most of the shifting is at WOT anyway). But in road racing, a BOV becomes more important. Also, the BOV is usually the loudest part in a turbo system, so for me anyway, I 'need' one for my street car because I want people to know that there is something diiferent about my IROC!

 

ahhh, i would much rather have the flutter after doing a big burnout...but i drag race and i use an auto so...

 

If you like the compressor surge noise, you ought to see a super stock diesel tractor pull (the smokers). They often have three or four turbos staged with up to (maybe some over) 200psi manifold pressure. Those turbos surge like mad when they back off after a run! Got to love that sound. I wouldn't mind if my IROC turbos would flutter like that, but for some reason, I can't get them to make any surge noise, even with no BOV. I suspect the ford probe intercoolers are a bit too restrictive.

BTW, anyone else on this board ever see a tractor pull? If you are into turbos you got to see them. I don't think there is any other more impressive display of turbo power than these guys. I mean, 200psi of boost- are they crazy?! Very impressive in my book.

 

Yea, not really a big ******* here (grew up in buffalo, and can’t believe how far south MD seems in attitude), but my dad took me to one when I was little and it made a lasting impression. The equipment/engines are just incredible, if you guys thing that “car guys” build some cool stuff, you need to check these things out.

Are you serious, r e d n e c k is censored???

 

From what I understand and what GN owners have told me, their engines work better with autos then manuals.

 

A rare a dying breed my friend for young people to think that way. But thats the way I look at it. I don't care what it sounds like as long as it works great.

 

Pretty much, turbos give you a broader power curve so there is more of an advantage to pulling harder over a longer range then taking the time to shift to stay in a narrower range. Also, with an auto it’s easier for most people to keep the boost up

 

Here is a Data log from a quick little run down a backstreet, I thought you guys might find interesting.

If you look where I let off the gas to shift to 2nd gear, you see the MAP fall from full boost to 26"~ of vacuum, and right back up to full boost. I am running twin 1G DSM BOV's, they keep the turbos going. I didnt HAVE to let off, I just did it for sake of data log.